Core: fix deprecation warning for utcnow() in setup.py (#4170)

setup.py

@@ -321,7 +321,7 @@ def run(self) -> None:
                                   f"{ex}\nPlease close all AP instances and delete manually.")
 
         # regular cx build
-        self.buildtime = datetime.datetime.utcnow()
+        self.buildtime = datetime.datetime.now(datetime.timezone.utc)
         super().run()
 
         # manually copy built modules to lib folder. cx_Freeze does not know they exist.